kernel BUG at fs/btrfs/ctree.c:2950
Hi, I have a torture test[1] that I run to test stable page writeback. When I run it against a btrfs (3.7.0-rc3) I observe the kernel bug messsage[2] that I've attached at the end of this message. The test program spawns a bunch of threads, which try to rewrite file blocks either through mmap or through regular pwrite calls. I'll take a look at it tomorrow, but I was wondering if this caught anybody's eye... # gcc -o wac wac.c # mount /dev/path/to/a/btrfs /mnt # ./wac -l 65536 -n 32 -m 32 -f -r /mnt/victimfile wait a few seconds kaboom --D [1] http://djwong.org/docs/wac.c [2] Double stack-trace: [ 9713.768350] [ cut here ] [ 9713.773188] WARNING: at /storage/home/djwong/cdev/work/linux-spw/fs/btrfs/tree-log.c:3716 btrfs_log_inode_parent+0x427/0x480 [btrfs]() [ 9713.778876] Hardware name: Bochs [ 9713.780877] Modules linked in: btrfs sd_mod scsi_debug ext4 mbcache jbd2 scsi_mod sch_fq_codel nfsv4 eeprom nfsd auth_rpcgss exportfs af_packet raid1 raid0 md_mod zlib_deflate libcrc32c [last unloaded: sd_mod] [ 9713.786778] Pid: 1992, comm: wac Not tainted 3.7.0-rc3-spw #42 [ 9713.789183] Call Trace: [ 9713.791102] [8105210f] warn_slowpath_common+0x7f/0xc0 [ 9713.793428] [8105216a] warn_slowpath_null+0x1a/0x20 [ 9713.795826] [a030ad57] btrfs_log_inode_parent+0x427/0x480 [btrfs] [ 9713.798310] [8117c97c] ? dget_parent+0x1c/0xe0 [ 9713.800653] [a030adf6] btrfs_log_dentry_safe+0x46/0x70 [btrfs] [ 9713.803149] [a02e21c6] btrfs_sync_file+0x1a6/0x240 [btrfs] [ 9713.805626] [81550f49] ? sysret_check+0x22/0x5d [ 9713.807861] [8119705d] do_fsync+0x5d/0x90 [ 9713.810077] [812595ae] ? trace_hardirqs_on_thunk+0x3a/0x3f [ 9713.812642] [81197460] sys_fsync+0x10/0x20 [ 9713.814793] [81550f1d] system_call_fastpath+0x1a/0x1f [ 9713.817178] ---[ end trace 47f6b9aede5fa6f5 ]--- [ 9715.884354] [ cut here ] [ 9715.888197] kernel BUG at /storage/home/djwong/cdev/work/linux-spw/fs/btrfs/ctree.c:2950! [ 9715.888197] invalid opcode: [#1] PREEMPT SMP [ 9715.888197] Modules linked in: btrfs sd_mod scsi_debug ext4 mbcache jbd2 scsi_mod sch_fq_codel nfsv4 eeprom nfsd auth_rpcgss exportfs af_packet raid1 raid0 md_mod zlib_deflate libcrc32c [last unloaded: sd_mod] [ 9715.888197] CPU 0 [ 9715.888197] Pid: 1990, comm: wac Tainted: GW3.7.0-rc3-spw #42 Bochs Bochs [ 9715.888197] RIP: 0010:[a02af5b9] [a02af5b9] btrfs_set_item_key_safe+0x149/0x150 [btrfs] [ 9715.888197] RSP: 0018:880028735ae8 EFLAGS: 00010246 [ 9715.888197] RAX: RBX: 000f RCX: e000 [ 9715.888197] RDX: RSI: 880028735c16 RDI: 880028735ac7 [ 9715.888197] RBP: 880028735b48 R08: 0c9e R09: 880028735b08 [ 9715.888197] R10: R11: R12: 880016b62bf0 [ 9715.888197] R13: 880028735c16 R14: 880028735b07 R15: 8800293edbd0 [ 9715.888197] FS: 7f3ffa3b3700() GS:88003fc0() knlGS: [ 9715.888197] CS: 0010 DS: ES: CR0: 8005003b [ 9715.888197] CR2: 7f3ffa3b0fba CR3: 2872d000 CR4: 07f0 [ 9715.888197] DR0: DR1: DR2: [ 9715.888197] DR3: DR6: 0ff0 DR7: 0400 [ 9715.888197] Process wac (pid: 1990, threadinfo 880028734000, task 88002870de50) [ 9715.888197] Stack: [ 9715.888197] 880028735b48 88002f678000 8800131c2000 0100 [ 9715.888197] 6c01 e000 880028735b48 8800293edbd0 [ 9715.888197] 880016b62bf0 d000 0001 [ 9715.888197] Call Trace: [ 9715.888197] [a02e46e7] __btrfs_drop_extents+0x557/0xb00 [btrfs] [ 9715.888197] [a0306fdd] btrfs_log_changed_extents+0x5bd/0x610 [btrfs] [ 9715.888197] [a02efff7] ? free_extent_buffer+0x37/0x90 [btrfs] [ 9715.888197] [a0308efb] btrfs_log_inode+0x50b/0x5b0 [btrfs] [ 9715.888197] [8117c9b8] ? dget_parent+0x58/0xe0 [ 9715.888197] [a030aac2] btrfs_log_inode_parent+0x192/0x480 [btrfs] [ 9715.888197] [8117c97c] ? dget_parent+0x1c/0xe0 [ 9715.888197] [a030adf6] btrfs_log_dentry_safe+0x46/0x70 [btrfs] [ 9715.888197] [a02e21c6] btrfs_sync_file+0x1a6/0x240 [btrfs] [ 9715.888197] [81550f49] ? sysret_check+0x22/0x5d [ 9715.888197] [8119705d] do_fsync+0x5d/0x90 [ 9715.888197] [812595ae] ? trace_hardirqs_on_thunk+0x3a/0x3f [ 9715.888197] [81197460] sys_fsync+0x10/0x20 [ 9715.888197] [81550f1d] system_call_fastpath+0x1a/0x1f [ 9715.888197] Code: 00 00 4c 89 f6 4c 89 e7 48 98 48 8d 04 80 48 8d 54 80 65 e8 aa 1b 04 00 4c 89 ee 4c 89 f7 e8 2f f2 ff ff 85 c0 0f 8f 57 ff ff ff 0f 0b 0f 0b 0f 1f 00 66 66 66 66 90 55 48 b8 00 00 00 00 00 16 [ 9715.888197]
Re: kernel BUG at fs/btrfs/ctree.c:2950
On thu, 1 Nov 2012 00:04:13 -0700, Darrick J. Wong wrote: Hi, I have a torture test[1] that I run to test stable page writeback. When I run it against a btrfs (3.7.0-rc3) I observe the kernel bug messsage[2] that I've attached at the end of this message. The test program spawns a bunch of threads, which try to rewrite file blocks either through mmap or through regular pwrite calls. I'll take a look at it tomorrow, but I was wondering if this caught anybody's eye... I'm looking into the following problem now, it seems that the file extent metadata is modified when we do logging. Thanks Miao # gcc -o wac wac.c # mount /dev/path/to/a/btrfs /mnt # ./wac -l 65536 -n 32 -m 32 -f -r /mnt/victimfile wait a few seconds kaboom --D [1] http://djwong.org/docs/wac.c [2] Double stack-trace: [ 9713.768350] [ cut here ] [ 9713.773188] WARNING: at /storage/home/djwong/cdev/work/linux-spw/fs/btrfs/tree-log.c:3716 btrfs_log_inode_parent+0x427/0x480 [btrfs]() [ 9713.778876] Hardware name: Bochs [ 9713.780877] Modules linked in: btrfs sd_mod scsi_debug ext4 mbcache jbd2 scsi_mod sch_fq_codel nfsv4 eeprom nfsd auth_rpcgss exportfs af_packet raid1 raid0 md_mod zlib_deflate libcrc32c [last unloaded: sd_mod] [ 9713.786778] Pid: 1992, comm: wac Not tainted 3.7.0-rc3-spw #42 [ 9713.789183] Call Trace: [ 9713.791102] [8105210f] warn_slowpath_common+0x7f/0xc0 [ 9713.793428] [8105216a] warn_slowpath_null+0x1a/0x20 [ 9713.795826] [a030ad57] btrfs_log_inode_parent+0x427/0x480 [btrfs] [ 9713.798310] [8117c97c] ? dget_parent+0x1c/0xe0 [ 9713.800653] [a030adf6] btrfs_log_dentry_safe+0x46/0x70 [btrfs] [ 9713.803149] [a02e21c6] btrfs_sync_file+0x1a6/0x240 [btrfs] [ 9713.805626] [81550f49] ? sysret_check+0x22/0x5d [ 9713.807861] [8119705d] do_fsync+0x5d/0x90 [ 9713.810077] [812595ae] ? trace_hardirqs_on_thunk+0x3a/0x3f [ 9713.812642] [81197460] sys_fsync+0x10/0x20 [ 9713.814793] [81550f1d] system_call_fastpath+0x1a/0x1f [ 9713.817178] ---[ end trace 47f6b9aede5fa6f5 ]--- [ 9715.884354] [ cut here ] [ 9715.888197] kernel BUG at /storage/home/djwong/cdev/work/linux-spw/fs/btrfs/ctree.c:2950! [ 9715.888197] invalid opcode: [#1] PREEMPT SMP [ 9715.888197] Modules linked in: btrfs sd_mod scsi_debug ext4 mbcache jbd2 scsi_mod sch_fq_codel nfsv4 eeprom nfsd auth_rpcgss exportfs af_packet raid1 raid0 md_mod zlib_deflate libcrc32c [last unloaded: sd_mod] [ 9715.888197] CPU 0 [ 9715.888197] Pid: 1990, comm: wac Tainted: GW3.7.0-rc3-spw #42 Bochs Bochs [ 9715.888197] RIP: 0010:[a02af5b9] [a02af5b9] btrfs_set_item_key_safe+0x149/0x150 [btrfs] [ 9715.888197] RSP: 0018:880028735ae8 EFLAGS: 00010246 [ 9715.888197] RAX: RBX: 000f RCX: e000 [ 9715.888197] RDX: RSI: 880028735c16 RDI: 880028735ac7 [ 9715.888197] RBP: 880028735b48 R08: 0c9e R09: 880028735b08 [ 9715.888197] R10: R11: R12: 880016b62bf0 [ 9715.888197] R13: 880028735c16 R14: 880028735b07 R15: 8800293edbd0 [ 9715.888197] FS: 7f3ffa3b3700() GS:88003fc0() knlGS: [ 9715.888197] CS: 0010 DS: ES: CR0: 8005003b [ 9715.888197] CR2: 7f3ffa3b0fba CR3: 2872d000 CR4: 07f0 [ 9715.888197] DR0: DR1: DR2: [ 9715.888197] DR3: DR6: 0ff0 DR7: 0400 [ 9715.888197] Process wac (pid: 1990, threadinfo 880028734000, task 88002870de50) [ 9715.888197] Stack: [ 9715.888197] 880028735b48 88002f678000 8800131c2000 0100 [ 9715.888197] 6c01 e000 880028735b48 8800293edbd0 [ 9715.888197] 880016b62bf0 d000 0001 [ 9715.888197] Call Trace: [ 9715.888197] [a02e46e7] __btrfs_drop_extents+0x557/0xb00 [btrfs] [ 9715.888197] [a0306fdd] btrfs_log_changed_extents+0x5bd/0x610 [btrfs] [ 9715.888197] [a02efff7] ? free_extent_buffer+0x37/0x90 [btrfs] [ 9715.888197] [a0308efb] btrfs_log_inode+0x50b/0x5b0 [btrfs] [ 9715.888197] [8117c9b8] ? dget_parent+0x58/0xe0 [ 9715.888197] [a030aac2] btrfs_log_inode_parent+0x192/0x480 [btrfs] [ 9715.888197] [8117c97c] ? dget_parent+0x1c/0xe0 [ 9715.888197] [a030adf6] btrfs_log_dentry_safe+0x46/0x70 [btrfs] [ 9715.888197] [a02e21c6] btrfs_sync_file+0x1a6/0x240 [btrfs] [ 9715.888197] [81550f49] ? sysret_check+0x22/0x5d [ 9715.888197] [8119705d] do_fsync+0x5d/0x90 [ 9715.888197] [812595ae] ? trace_hardirqs_on_thunk+0x3a/0x3f [ 9715.888197] [81197460]
